> A new draft of the CSS3 module "multi-column layout" has been
> published.
I find myself somewhat concerned by this spec. Okay, it's only a
draft, so many details are missing, but some of the *implied*
changes to layout algorithms seem to make things very tricky
indeed.
A change in flow from one column to the next can seemingly occur
in the middle of inline content. Meaning a block is no longer a
rectangle; it can span any arbitrary collection of rectangles.
This has implications for border, margin, background alignment
and so on that should be specified. It makes positioning and
scripting difficult - how can you read/set the position and
size of a rectangle that's split over three columns, for example?
It seems to me that multi-column layouts are most useful for
print media rather than a scrolling viewport. But how do
multi-column layouts work over page breaks? Does the break
force column balancing? Do the page-break-* properties of
children work relative to the page? Do we need column-break-*
properties? Can you put a multi-column layout inside another
multi-column layout? Could multi-page layouts be considered
a special case of multi-column layout?
The multi-column spec as outlined here looks nice and simple,
but what happens when it's combined with positioning? Bi-di?
Ruby? mid-column floats are nice, but what happens when
there's not enough space for them? When they get in the way
of a standard floating element? Column-span is handy, but
it seems to also affect how many columns the *previous*,
not-spanned elements take up. Can a "column-span: 2" element
also run through a second double-width column, filling
four columns in all?
I'm sure there's many more subtleties I haven't yet seen,
but already this is making the task of layout extremely
complex, for a feature I personally believe is of limited
usefulness on the web. Multi-column layouts are great for
paper, but in a window that you have to scroll down to
read, they're only practical for relatively small amounts
of text, otherwise you'd have to keep scrolling down and
up again to get through it.
Sorry if this sounds overly critical; these are just the
objections that came to mind whilst reading the spec. There
are, OTOH, many things I *do* like in the spec, like the way
the number of columns isn't (as I had feared) fixed. I just
didn't mention them. :-)
--
Andrew Clover
Technical Support
1VALUE.com AG